Just a big thanks to everyone for help advice. Mum started clickering her yesterday, and although she was in a terrible temper at the time, when mum had finished, she was all sweetness and light, and even this morning she was still being lovely – she even put her ears forward when mum went in to give her her breakfast!!!
If anyone else has the same problem – here’s the link to Alexandra Kurland’s site about “mouthy horses”
http://theclickercenter.com/2004/guide/guide09.php
I’ll be mostly scouring there for the next few months!!